This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Oviduct-specific glycoprotein (OGP), also known as oviductin or MUC9, is a major mucin-like glycoprotein synthesized and secreted by non-ciliated secretory cells of mammalian oviducts. Oviduct-specific glycoprotein is conserved among all species examined to date including humans. The synthesis and secretion of OGP are under estrogen control. In vitro functional studies showed that OGP plays important roles during fertilization and early embryo development.